Flow Cytometry Core Abstract The Flow Cytometry Core will provide expertise in stem cell separations, cell sorting and cell phenotyping analysis. The Core will be co-directed by Dr. Loren Fast and Mr. Mark Dooner. Mr. Dooner is an experienced flow cytometrist with sorting and analysis of neural and hematopoietic stem cells, and will oversee the daily operation including cell sorting and analysis. Dr. Fast will serve as an advisor and resource to the investigators for experimental design, data interpretation and manuscript preparation. During Phase I, instrument upgrades created a five laser cell sorter that is unique in the Rhode Island research community. This Core features an Influx high speed cell sorter (BD Biosciences). This sorter is capable of carrying out stem cell separations, single cell deposition, and simultaneous six-way sorting and is housed within a biosafety cabinet. This Core is housed in a newly constructed and dedicated suite. The facility is equipped with a LSRII flow cytometer (BD Biosciences) with FACS Diva software for cell cycle analysis and routine flow cytometry analysis. Investigators will work with the Core and prepare their cell populations for sorting or analysis. The Core will serve all projects in this COBRE carrying out both separations and analysis work free of charge. Non-COBRE investigators are making use of the Core on a fee for service basis however COBRE Projects will be given priority. The Core remains dedicated to the development of new separation techniques and the enhancement of known neural and hematopoietic stem cell populations.